DETAILED STEPS

1. Pick up the handset of an attached telephony device and check for a dial tone.

2. If you have dial tone, check for DTMF detection. If the dial tone stops when you dial a digit, then the voice port is most likely configured properly for DTMF detection.

3. To identify port numbers of voice interfaces installed in your router, use the show voice port summary command.

4. To verify voice-port parameter settings, enter the show voice port command with the appropriate syntax for your voice interfaces.

5. For digital T1/E1 connections, to verify the codec complexity configuration, enter the show running-config command to display the current voice-card setting. If medium complexity is specified, the codec complexity setting is not displayed. If high complexity is specified, the setting codec complexity high is displayed. The following example shows an excerpt from the command output when high complexity has been specified:

6. For digital T1/E1 connections, to verify that the controller is up and that no alarms have been reported, and to display information about clock sources and other controller settings, use the show controller command. For output examples, see the show controller Samples.

Router# show controller {t1 | e1} controller-number

7. To display voice-channel configuration information for all DSP channels, enter the show voice dsp' command'. For output examples, see the show voice dsp Samples.

Router# show voice dsp

8. To verify the call status for all voice ports, enter the show voice call summary' command'. For output examples, see the show voice call summary Samples.

Router# show voice call summary

9. To display the contents of the active call table, which shows all of the calls currently connected through the router or concentrator, enter the 'show call active voice' command. For output examples, see the show call active voice Samples.

Router# show call active voice

10. To display the contents of the call history table, enter the show call history voice' command'. To limit the display to the last calls connected through this router, enter the keyword last and define the number of calls to be displayed with the argument number. To limit the display to a shortened version of the call history table, use the keyword brief. For output examples, see the show call history voice Sample.

Router# show call history voice {last | number | brief}

show voice port Samples

In the following sections, output examples of the following types are shown:

Cisco 3600 series digital E&M voice port

Cisco AS5300 universal access server T1 CAS voice port

Cisco 7200 series router digital E&M voice port

Cisco 3600 Digital E&M Voice Port

Router# show voice port 1/0:1
receEive and transMit Slot is 1, Sub-unit is 0, Port is 1
Type of VoicePort is E&M
Operation State is DORMANT
Administrative State is UP
No Interface Down Failure
Description is not set
Noise Regeneration is enabled
Non Linear Processing is enabled
Music On Hold Threshold is Set to -38 dBm
In Gain is Set to 0 dB
Out Attenuation is Set to 0 dB
Echo Cancellation is enabled
Echo Cancel Coverage is set to 8 ms
Connection Mode is normal
Connection Number is not set
Initial Time Out is set to 10 s
Interdigit Time Out is set to 10 s
Region Tone is set for US

Cisco AS5300 Universal Access Server T1 CAS Voice Port

Router# show voice port
DS0 Group 1:0 - 1:0
Type of VoicePort is CAS
Operation State is DORMANT
Administrative State is UP
No Interface Down Failure
Description is not set
Noise Regeneration is enabled
Non Linear Processing is enabled
Music On Hold Threshold is Set to -38 dBm
In Gain is Set to 0 dB
Out Attenuation is Set to 0 dB
Echo Cancellation is enabled
Echo Cancel Coverage is set to 8 ms
Playout-delay Mode is set to default
Playout-delay Nominal is set to 60 ms
Playout-delay Maximum is set to 200 ms
Connection Mode is normal
Connection Number is not set
Initial Time Out is set to 10 s
Interdigit Time Out is set to 10 s
Call-Disconnect Time Out is set to 60 s
Ringing Time Out is set to 180 s
Companding Type is u-law
Region Tone is set for US
Wait Release Time Out is 30 s
Station name None, Station number None
Voice card specific Info Follows:
DS0 channel specific status info:
IN OUT
PORT CH SIG-TYPE OPER STATUS STATUS TIP RING

Cisco 7200 Series Router Digital E&M Voice Port

Router# show voice port 1/0:1
receEive and transMit Slot is 1, Sub-unit is 0, Port is 1 << voice-port 1/0:1
Type of VoicePort is E&M
Operation State is DORMANT
Administrative State is UP
No Interface Down Failure
Description is not set
Noise Regeneration is enabled
Non Linear Processing is enabled
Music On Hold Threshold is Set to -38 dBm
In Gain is Set to 0 dB
Out Attenuation is Set to 0 dB
Echo Cancellation is enabled
Echo Cancel Coverage is set to 8 ms
Connection Mode is normal
Connection Number is not set
Initial Time Out is set to 10 s
Interdigit Time Out is set to 10 s
Region Tone is set for US

show controller Samples

In the following sections, output examples of the following types are shown:

Verifying Digits Received and Sent on the POTS Call Leg

Once the on-hook and off-hook signaling are verified to be working correctly, verify the correct digits are being received or sent on the digital voice port. A dial peer that does not matched or the switch (CO or PBX) cannot ring the correct station if incomplete or incorrect digits are being sent or received. Some commands that can be used to verify the digits received or sent are:

show dialplan number-This command is used to show which dial peer is reached when a particular telephone number is dialed.

debug vtsp session-This command displays information on how each network indication and application request is processed, signaling indications, and DSP control messages.

debug vtsp dsp-This command displays the digits as they are received by the voice port.

show dialplan number

The show dialplan number command displays the dial peer that is matched by a string of digits. If multiple dial-peers can be matched, they are all shown in the order in which they are matched. The output of this command looks like this:

If the digits are not being sent or received properly, then it might be necessary to use either a digit-grabber (test tool) or T1 tester to verify that the digits are being sent at the correct frequency and timing interval. If they are being sent "incorrectly" for the switch (CO or PBX), some values on the router or switch (CO or PBX) might need to be adjusted so that they match and can interoperate. These are usually digit duration and inter-digit duration values.

Another item to examine if the digits appear to be sent correctly are any number translation tables in the switch (CO or PBX) that may add or remove digits. Refer to your switch documentation to check the translation tables on your switch.